Answer;
One scientific belief held by both Rene Descartes and Isaac Newton is that the reasoned thought is the way to discover truth.
Explanation;
Rene Descartes used deductive reasoning, deducing a conclusion from a set of premises, to determine the nature of the universe, that was contrary to other great thinkers of the time who used scientific observation.
Sir Isaac Newton; specialized in uniting experimental and theoretical elements of modern science.
They wrote a new constitution.
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